Core catcher



Oct. 4, 1938. A. c. CATLAND CORE CATCHER Filed sept. 25, 195s Patented Oct. 4, 193gv UNITED STATES f-UPATENT ori-lcs Application september 25, 193s, serial-No. 102,528

12 Claims.

This invention relates to well drilling tools and relates more particularly to a core catcher for use in a well core drill. A general object of this invention is to provide a practical dependable and v ery effective core'catcher for use in a rotary core drill.

Another object of this invention is to provide improvements in core catchers o'f the general type set `forth in Patent No. 2,063,437, issued De.

cember 8, 1936. I

Another object of this invention is to provide a core catcher of the character mentioned operable to dependably retain and recover a core with a minimum of mutilation oi the same.

Another object of this invention is to provide a core catcher embodying slips positioned and mounted sov that they do not injure or foul the core when it is received in the drill.

Another object of this invention is to provide an improved core catcher embodying a combina.- tion of slips for gripping the core, a control ring connected with the slips to4 assure their simultaneous actuation and spring arms connected with the ring to assist in controlling the slips and gripping the core.

Another object of this invention is to provide a core catcher of thecharactermentioned in which the assembly of the control ring and the spring arms is light in weight so that its momentum does not tend to prematurely actuate the slips when the drill is run into the well.'

Another object of this invention is to provide a core catcher of the type mentioned that is not made inoperative by accumulations of mud, cuttings, etc.

A further object of this invention is to provide a core catcher of the' character'mentioned in which the slips are received in grooves so that they do not scrape mud and sand from the core, which might interfere with their proper operation.

The various objects and features of my invention will be fully understood from the following detailed description of a typical preferred form and application of my invention, throughout which description reference is made to the accompanying drawing, in which:

Fig. 1 is a central longitudinal detailed sectional view of a well core drill embodying the core catcher of the present invention. Y -l""ig. 2 is an enlarged fragmentary longitudinal `detailed sectional view of a portion of the drill and core catcher illustrating the slips in their unactuated positions and Fig. 31s anenlarged transverse detailed sectional view taken as indicated by line 3 3 on Fig. 1.

The improved core catcher ofthe present invention is adapted to be employed in core drills of various forms and types. In the following detailed disclosure I will describe a typical form ofthe invention as employed in a core drill of the type fully described and claimed in my co-pending application entitled Core drill, filed August 12, 1936, Serial No. 95,513, Patent No. 2,093,633, issuedSeptember 21, 1937. It is to be understood that the invention is not to be construed as limited or restricted to the specific form or application about to be described.

The core drill illustrated in thedrawing includes an outer barrel I adapted to be connected with the lower end of a rotary well drilling string. A sub Il is threaded on the lower end of the barrel I0 a'nd carries a tubular bit head sub I2. A bit head I3 is threaded on the lower end of the sub I2. The particular bit head I3 illustrated has a, plurality of spaced roller cutters I 4 set in recesses in its lower end. The bit head I3 has a central vertical opening I 5 for receiving the core. A tube or sleeve I6-is arranged longitudinally through the sub I2. The lower end of the sleeve I6 may restl on a shoulder I'I in the bit headl3. 'I'he sleeve I6 extends upwardly to a point adjacent the lower end of the sub I I. The upperprtion of the sleeve I5 is internally stepped hjavlng three vertically spaced upwardly facingfshoulders I8, I9 and 20. The sleeve I6 -is spaced from the interior of the sub I2 leaving an annular iluid through the outer barrel I0 to receive the core.

'I'he barrel 25 is spaced from the interior of the outer barrel l0 leaving an annular fluid passage P. A bearing collar 26 is xed to the lower end of the inner barrel 25 and extends downwardly into the sleeve I6. 'I'he lower end of the collar 26 may rotatably bear on the shoulder I8. Ports 2l in the c ollar 26 connect the lower end of the passage P with the upper end of the passage 2l. An annular recess 28 extends upwardly in the collar 26 from its lower end. -The particular drill illustrated embodies a dog-type core catcher .29 rotatably supported in the bit Y The present invention is not primarily concerned with the details of the core catcher 29 and such details are omitted from the description.

The corel catcher of the present invention includes, generally, a free sleeve 30 arranged in the sleeve I6, a ring 3| in the sleeve I6 below the Asleeve 30, slips 32 connected with the ring 3| and operable through cooperation with the sleeve 30, and Ispring arms 33 on the ring 3| for cooperating with the core.

The sleeve. 30 is provided to present inclined abutments for actuating the slips 32. In accordance with the invention the sleeve 30 may be a simple, tubular. one piece member, as illustrated. It is a feature of the invention that the sleeve 30 may be of uniform wall thickness throughout its length. In practice the sleeve 30 may be comparatively thick walled. The sleeve 30 is provided with nat upper and lower ends and concentrically curved internal and external surfaces. The sleeve 30 is arranged within the sleeve I6 between the shoulder I9 and the upper wall of the recess 28 in the collar 26, its upper portion being received in the recess. 'Ihe sleeve 3G is proportioned to be free to turn or remain stationary in the sleeve I6 at will. The internal diameter of the sleeve 3D is4 such that the sleeve may freely pass the core' during the coring operation. Longitudinal movement of the sleeve 30 is prevented or limited by the shoulder I9 and the upper wall of the recess 28.

cordance with the invention the grooves 34 may.

have flat parallel side walls. The inner walls or bottom walls 35 of the grooves 34 are inclined downwardly and inwardly relative to the longitudinaliaxis of the drill. Due to the inclination of their bottom walls 35 the grooves 34 are of substantial depth at their upper ends and terminate some distance above the lower end of the sleeve 30. The grooves 34 are preferably identical.

The ring 3| is provided to carry the spring arms 33 and to assure the simultaneous actuation of the several slips 32. It is a feature of the invention that the ring 3| may be a simple, light weight member. The ring 3| is arranged within the sleeve I6 at the lower end of the sleeve 30 and is proportioned to be free to rotate or to remain stationary at will. The opposite ends of the ring 3| may be lfiat and parallel as illustrated. The ring 3| may be of substantially the same internal diameter as thesleeve'lll.

The slips 32 are provided to grip and support the core whenthe drill is raised after the drilling operation. A'The slips 32 are in the nature of toothedwedges operable longitudinally in the grooves 34. In accordance with the invention the slips 32 have flat parallel sides for shiftably cooperating with the side walls of the grooves 34. 'I'he active sides or inner sides o1' the slips 32 may be concave to conform, generally, to the core and are provided with teeth 36 for gripping the core. The slips are proportioned'to be substantially entirely received in the grooves 34 when in their retracted up positions and to project inwardly a substantial distance from the lgrooves when in their down, actuated positions. The slips 32 are provided with downwardly and inwardly inclined surfaces 31 for shiftably bearing on the bottom walls 35 of the grooves 34. During relative vertical movement between the sleeve 30 and the slips 32 in one direction the cooperation of the walls 35 and surfaces 31 effects the inward displacement or movement of the slips 32 to bring their,teeth 36 into gripping engagement with the core.

Means is provided for connecting the slips 32 with the ring 3| whereby the slips are connected for simultaneous operation and are controlled or actuated through the engagement of the spring arms 33 with the core. The means for connecting the slips 32 with the 'ring 3| includes spring members or reins 38 secured to the interior of the ring 3| and projecting upwardly through the sleeve 30 and grooves 34 to the slips 32. Suitable rivets 39 may rigidly secure the reins 38 to the ring 3|. The reins 38 are proportioned to support the slips 32 in the upper portions of the grooves 34 when the ring 3| is at the lower end of the sleeve 30, as illustrated in Figs. 1 and 2.

The spring arms 33 are provided on the ring 3| to resist relative movement between the ring and the core when the drill is raised so that the upward movement of the drill causes the walls 35 of the grooves 34 to actuate the lslips 32 inwardly against the core. 'I'he spring arms 33 also assist in gripping and supporting the core. The spring arms 33 are in the nature of strap or leaf springs and are secured to the interior of the ring 3| to project upwardly and inwardly from the ring. In accordance with the invention the spring arms 33 may be secured .to the ring 3|' by the rivets 39, as illustrated throughout the drawing. The upper end portions of the spring arms 33 may be rather sharply inclined inwardly and may be bevelled to better cooperate formation leaving a core which is received in the opening I5. As the drilling progresses the core is received in the sleeve I6 and passes throughthe core catcher of the present invention into the inner barrel 25,. During the passage of the core through the core catcher the spring arms 33 yieldingly engage the core and their engagement with the core holds the ring 3| upwardlyl against the lower end of the sleeve 30. Thus the engagement of the spring arms 33 with the core may hold the slips 32 in their uppermost positions where they do not contact or engage the core. As described above, the slips 32 are substantially entirely received in the upper portions of the grooves 34 when in their uppermost positions, and, therefore, cannot foul or mutilate the core during the coring operation. Further,

reins 38. The shoulder I9 engaging the lower y end of the sleeve 30 causes the sleeve to move upwardly with the drill. The inclined walls 35 on the upwardly moving sleeve 30 cooperate with the inclined surfaces 31 on the slips 32 which are held against movement as described above. The cooperation of the walls 35 and the surfaces 31 3,132,014 eects inward displacement or actuation of the' any variations or modifications that may appear to those skilled in the art or fall within the scope of the following claims:

Having described my invention, I claim:

1. A core catcher for use in the core receiving opening of a Well drill comprising, a sleeve for arrangement in the opening, the sleeve having longitudinal grooves provided with inclined inner walls, slips movable in the grooves and operable through cooperation with said walls, and a spring connected with the slips and engageable with the core for controlling the operation of the slips. Y

2. A core catcher for use in the core receiving opening of a well drill comprising, `a sleeve of substantiallyuniform wall thickness for arrangement in the opening, the sleeve having longitudi nal grooves provided with inclined inner walls. slips movable in the grooves and operable through cooperation 'with said walls, and spring means engageable with the core and connected with the slips ,for controlling the operation of the slips.

, 3. A core catcher for use in the core receiving opening o f a well drill comprising, a sleeve for arrangement in the opening, the sleeve having positions, and core engaging means controlling the actuation of the slips", 'said means comprising core engaging spring arms connected with the slips.

4. A core catcher for use in the core receiving opening of a well drill comprising, a sleeve for arrangement in the opening, the sleeve having longitudinal grooves provided with inclined inner walls, slips movable in the grooves and operable through cooperation with said walls, and means controlling the operation of the slips, said means including, a free ring below the sleeve, and reins connecting the slips with the ring.

5. A core catcher for use in the core receiving opening of a welldrill comprising, a sleeve for arrangement in the opening, the sleeve having longitudinal grooves provided with inclined inner walls, slips-movable in the grooves and operable through cooperation with said walls, and means controlling the operation of the slips, said means including a free ring below the sleeve, reins connecting the slips with the ring, and core engaging parts on the ring.

6. A core catcher for use in the core receiving opening of a well drill comprising, a sleeve of substantially uniform wall thickness arranged in the drill to move vertically therewith, the sleeve having longitudinal internal grooves with downwardly and inwardly inclined bottom walls whereby theylhave the greatest depth at their upper ends, longitudinally movable slips in the grooves initially substantially entirely within the deep pnrtions of the grooves and operable inwardly against the core by said walls upon upward movement of the sleeve with the drill, and core engaging spring arms connected to the slips for resisting upward movement of the slips.

7. A core catcher for use in the core receiving opening of a well drill comprising, a sleeve of substantially uniform wall thickness, the sleeve having longitudinal internal grooves with downwardly and inwardly inclined" bottom walls whereby they have the greatest depthat their upper ends, longitudinally movable slips in the grooves initially substantially entirely within the deep portions of the grooves and operable inwardly against the core by said walls upon movement of the sleeve, and means resisting upward movement of the slips, said means including, a ring in the opening below the sleeve, reins connecting the slips with the ring, and core engaging members on the ring for resisting movement of the ring.

8. A core catcher for use in the core receiving ,opening of a well drill comprisingzf a sleeve of substantially uniform wall thickness arranged in the drill to move vertically therewith, the sleeve having longitudinal internal grooves with down wardly and inwardly inclinedA bottom walls whereby they have the greatest depth at their upper ends, longitudinally movable slips in the grooves initially substantially entirely within the deep portions of the grooves and operable inwardly against the core by said walls upon upward movement of the sleeve with the drill, and

means resisting upward movement'of the slips," said means including, a ring in the opening below thesleevereinsconnecting the slips with the ring, and core engaging spring arms on the ring for resisting movement of the ring.

9. A core catcher for use in the core receiving 'opening of a well drill comprising, a sleeve ar# ranged in the opening to move vertically with the drill, downwardly and inwardly inclined internal surfaces on the sleeve, core gripping slips actuated inwardly by said surfaces upon upward movement of the sleeve, a free ring in the opening below the' sleeve, reins connecting the slips with the ring, and resilient parts on the ring cooperating with the core to resist upward movement of the ring during upward movement of the sleeve.

10. A core catcher for use in the core receiving opening 4of a well drill comprising, a sleeve-arranged in the opening to move vertically with the drill, downwardly and inwardly inclined internal v surfaces on the sleeve, core gripping slips actu-- ternal surfaces on the sleeve, core gripping slips actuated inwardly by said surfaces upon upward movement of the sleeve, a free ring in the opening below the sleeve, reins attached to the slips, members attaching the reins to the ring, and spring arms for engaging the core attached to the ring by said members to resist movement of the ring during upward movement of the sleeve. 12.- A core catcher for use in the core receiving opening voi? .a well drill comprising,`a sleeve ot movement of the sleeve, and means resistingl upward movement of the slips, said means including, a free ring in the opening' below the sleeve, reins attached to slips, members attaching the reins to the ring, and spring arms attached to the ring by said members and operable to engage the core to resist movement of the ring duringupward movement of the sleeve.

ALFRED C. CATIAND. 

